Appendix C SIP Call Flows

 

 

 

Call Flow Scenarios for Successful Calls

 

Table C-5 Action Descriptions

 

 

 

 

 

 

 

 

 

Step

Action

Description

 

 

 

 

 

Step 1

INVITE—Cisco IP Phone A to SIP server

Cisco IP Phone A sends a call session

 

 

 

INVITE request to the SIP server to pass on to

 

 

 

Cisco IP Phone B.

 

 

 

 

 

Step 2

100 Trying—SIP server to Cisco IP Phone A

SIP server returns a 100 trying message,

 

 

 

indicating that the INVITE request has been

 

 

 

received.

 

 

 

 

 

Step 3

INVITE—SIP server to Cisco IP Phone B

SIP server sends the call session INVITE

 

 

 

request to Cisco IP Phone B.

 

 

 

 

 

Step 4

100 Trying—Cisco IP Phone B to SIP server

Cisco IP Phone B returns a 100 trying

 

 

 

message indicating that the INVITE request

 

 

 

has been received.

 

 

 

 

 

Step 5

180 Ringing—Cisco IP Phone B to SIP

Cisco IP Phone B sends a 180 ringing

 

 

server

response to the SIP server to pass on to

 

 

 

Cisco IP Phone A.

 

 

 

 

 

Step 6

180 Ringing—SIP server to Cisco IP Phone

SIP server sends the 180 ringing response to

 

 

A

Cisco IP Phone A.

 

 

 

 

 

Step 7

200 OK—Cisco IP Phone B to SIP server

Cisco IP Phone B sends a 200 OK message to

 

 

 

the SIP server indicating that a connection has

 

 

 

been established.

 

 

 

 

 

Step 8

200 OK—SIP server to Cisco IP Phone A

SIP server passes the 200 OK message to

 

 

 

Cisco IP Phone A.

 

 

 

 

 

Step 9

ACK—Cisco IP Phone A to SIP server

Cisco IP Phone A sends acknowledgement of

 

 

 

the 200 OK response to the SIP server to pass

 

 

 

on to Cisco IP Phone B.

 

 

 

 

 

Step 10

ACK—SIP server to Cisco IP Phone B

SIP server passes ACK response to

 

 

 

Cisco IP Phone B.

 

 

 

 

 

A two-way voice path is established between Cisco IP Phone A and Cisco IP Phone B.

 

 

 

 

 

Step 11

BYE—Cisco IP Phone A to SIP server

Cisco IP Phone A terminates the call session

 

 

 

and sends a BYE request to the SIP server

 

 

 

indicating that Cisco IP Phone A wants to

 

 

 

terminate the call.

 

 

 

 

 

 

 

 

 

Cisco IP Phone Models 7905G and 7912G Administrator Guide (SIP)

 

 

 

 

 

 

 

OL-4277-01

 

 

C-9

 

 

 

Page 191
Image 191
Cisco Systems 7912G, 7905G manual Table C-5 Action Descriptions

7912G, 7905G specifications

Cisco Systems is a leading provider of networking and telecommunications equipment, and among its extensive range of products, the Cisco 7900 Series of IP phones has made a notable impact in enterprise communication. Key models in this series include the Cisco 7905G, 7912G, and 7902G, each designed to enhance productivity through advanced features, intuitive interfaces, and robust technology.

The Cisco 7905G is designed for basic telephony needs and is ideal for administrative environments or areas with high call volumes. It features a large single-line LCD display, providing users with clear visibility of call information. The phone supports Power over Ethernet (PoE), making installation easier and reducing clutter by eliminating the need for an additional power supply. Its hands-free and headset support enhances user convenience, allowing for easy multitasking during calls.

Moving on to the Cisco 7912G, this model is designed for more demanding communication requirements. It features a larger, backlit display, providing improved visibility in various lighting conditions. The Cisco 7912G supports up to 12 programmable line or feature keys, giving users the flexibility to tailor the phone to their specific needs. Additionally, it incorporates advanced audio technologies, such as wideband audio for enhanced voice clarity and a built-in speakerphone, allowing users to communicate effectively in busy environments.

The Cisco 7902G, while offering basic features, is a reliable choice for users who need straightforward, cost-effective telephony solutions. It features an intuitive design with three dedicated buttons for line status, a built-in speakerphone, and support for wideband audio. The phone is geared for users who require essential telephony features without the complexity of additional functionalities, making it suitable for front-desk and general office use.

Overall, these models within the Cisco 7900 series exemplify the company's commitment to providing high-quality enterprise communication tools. With a focus on advanced audio technologies, user-friendly interfaces, and adaptability to various business environments, the Cisco 7905G, 7912G, and 7902G cater to the diverse needs of modern organizations. As companies continue to pursue seamless communication, these IP phones remain a valuable asset in their telephony infrastructure, enhancing collaboration and productivity among teams everywhere.